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1.2 Application
This Guide primarily provides assistance for developing maintainability programs according to the requirements of SAE
Standard JA1010. Implementation of the guide will help to answer questions frequently asked by suppliers and
customers such as:
a. Who is responsible for maintainability goals, planning, etc.?
b. What maintainability methods are most effective, and how are they applied?
c. When are maintainability methods used most effectively in the product development cycle?
d. Where can we get more detailed information and instructions on how to use the maintainability methods?
This Guide may also be used as a general reference for maintainability methods and maintainability program
management. Suppliers and customers may also find the Guide useful for other purposes such as those listed below:
a. Resource for design and manufacturing engineers to select available maintainability methods.
b. Provide an understanding of various maintainability program activities.
c. Provide assistance to suppliers who need knowledge of various maintainability methods and techniques, or
assistance establishing a formal maintainability program.
d. Assistance in planning, scheduling and structuring their maintainability programs.
e. Knowledge of available maintainability methods, a description of what they accomplish, and when they are best
applied.
f. Evaluating potential benefits and limitations of maintainability methods.
g. Practical method selection criteria.
1.2.1 Background
Maintainability is a discipline that has increased in importance as systems have become more complex, support costs
have increased, and resources have decreased. Maintainability is important in all product sectors, where high levels of
maintainability are increasingly becoming an important factor in production and customer cost of ownership.
Maintainability has been a recognized discipline for many years. Achieving the high levels of maintainability needed in
military and complex industrial and commercial systems is often difficult to accomplish. System complexity, competing
performance requirements, the rush to incorporate promising/immature technologies, the pressures on acquisition budget,
and schedule compression contribute to the degree of difficulty.
The information in this guide reflects both the move to incorporate commercial "best practices" and the lessons learned
over many years of former acquisition practices. When appropriate, commercial and military standards are cited herein for
reference. Whereas many of these documents emphasize what to do and how to do it, this guide focuses on the
objectives of a sound maintainability program and the engineering tools and techniques available to meet these
objectives.
SAE JA1010 uses only the terms “customer” and “supplier”. It is important to understand that this can represent the
relationship between the “end consumer” (customer) and “the company that produces the end product” (supplier) and
equally that between “the company that produces the end product” (customer) and “the company that produces a sub-
system” (supplier). For continuity therefore only “customer” and “supplier” are used throughout. When interpreting the
Program Requirements and the activities therein, it is necessary to keep in mind the applicable context and the parties
being discussed.
1.2.2 What Is Maintainability
The definition of Maintainability is defined slightly different in various standards, guides and text books. The definition
used in this document is taken from MIL-HDBK-470A, Designing and Developing Maintainable Products and Systems.
This definition can be modified by a customer or supplier and agreed to by them to reflect the specific product or system.
Definition of Maintainability - The relative ease and economy of time and resources with which an item can be retained in,
or restored to, a specified condition when maintenance is performed by personnel having specified skill levels, using
prescribed procedures and resources, at each prescribed level of maintenance and repair. In this context, it is a function
of design.
Maintainability, in some industries referred to as serviceability, is a design parameter. Although other factors, such as
properly trained personnel and a responsive supply system, can help keep downtime to a minimum, it is the inherent
maintainability that determines this minimum. Improving training or support cannot effectively compensate for the effect
on availability of a poorly designed (in terms of maintainability) product. Minimizing the cost to support a product, and
maximizing the availability of that product are more efficiently done by designing the product to be reliable and
maintainable.
Testability, an important subset of maintainability, is a design characteristic that allows the status (operable, inoperable or
degraded) of an item to be determined, and faults within the item to be isolated, in a timely and efficient manner. The
ability to detect and isolate faults within a system, and to do so efficiently and cost effectively, is important not only in the
field, but also during the testing phases of manufacturing. The expected percentage of faults that can be detected and
isolated to a specified or desired level of ambiguity must be determined. The consequences of poor testability include
higher manufacturing product test costs, higher support costs, and lower customer confidence and satisfaction.
1.2.3 Framework For a Maintainable Product Development
Suppliers should construct maintainability development programs that fit the customer needs. It is clear that, prior to
building a product, customer needs must be understood. Without proper information about customer needs, development
activities tend to lack focus and are likely to generate a poor design solution. Therefore, to ascertain the needs of the
customer becomes an important objective towards the goal of customer satisfaction. Once the needs have been
ascertained, a product that satisfies those needs can be produced. Therefore, the second objective of maintainable
product development is to meet the customer needs. Integral with the maintainability development program is the need to
verify and validate the requirements throughout the design process. Therefore, the third objective is to assure the
customer that the needs are met. These three objectives form the basis for a framework that underlies the SAE JA1010,
Maintainability Program Standard. This standard represents today’s prevalent thinking of how to develop maintainable
products and emphasizes the supplier-customer relationship among companies and their suppliers as well as among
end-consumers and companies. Table 1 provides the framework for the development of a maintainable product. The
three objectives listed above are set in SAE JA1010 as Program Requirements and are worded as follows:
The supplier shall ascertain customer requirements
The supplier shall meet customer requirements
The supplier shall assure that customer requirements have been met
Each program requirement further consists of a number of activities. These activities are accomplished by a number of
possible maintainability methods. It is essential to understand that maintainability transcends several disciplines across
many industries. Therefore, it is important not to be prescriptive about the specific maintainability methods used in product
development. Consequently, SAE JA1010 does not specify the maintainability methods to be used. Rather, the customer
and supplier(s) must work together to develop a maintainability program that completes each activity through the use of
mutually acceptable maintainability methods.
It should be recognized that SAE JA1010 uses the term "customer" to mean the end-user or a company. For example,
the user of a lawn tractor is a customer of the dealer and manufacturer. A company may also be a customer. For
example, an auto manufacturer is the “customer” of its instrument panel supplier. Also, there could be multiple or
intermediate customers to a supplier. Therefore, when interpreting the program requirements and the activities therein,
one needs to keep in mind the applicable context and the parties being discussed.
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1.2.3.1 The Supplier Shall Ascertain Customer Requirements
Understanding the customer’s maintainability needs is the first and most obvious step in meeting the objective of a
maintainable product. It is important that the level of maintainability addressed here is that which is measured by the
customer, not necessarily that measured during design and development. An important part of understanding customer
needs is to collect and study lessons learned on prior products, preferably products similar to the one being acquired or
manufactured. By learning which problems have plagued products or processes in the past, the maintainability engineer
can adopt design approaches that reduce, if not eliminate, those problems in the new product or processes.
Dialogue between customer and supplier should take place to gain a clear understanding of the product life cycle,
operating profile and environmental conditions. This discourse should cover the wider aspects of the maintenance policy,
future maintenance resources, integration with related functions and identification of possible trade-offs and risks. A
mutually agreed set of requirements that accurately reflects the intended performance and use of the product should be
the aim at this stage in the project. Supplier/customer information interchange should identify all the appropriate activities
needed for inclusion into a maintainability program that ensure the customers’ requirements will be met. The
maintainability program is discussed in detail in Section 4.
Suppliers must understand customer needs to determine product functions, the conditions it has to perform within the
expected performance duration and the in-service support policy. The input from customers may not always be in a form
that allows direct interpretation in terms of technical design. Furthermore, inputs may come from multiple customers.
Therefore, supplier engineers need to translate the input into the desired technical parameters to be able to achieve the
required product functionality. Thus, the activities defining this JA1010 Program Requirement include:
a. Establish Supplier-Customer Dialogue
b. Identify Conditions of Use
c. Define Maintenance and Service
d. Establish Metrics
e. Develop Product Specification
f. Operating Environment
1.2.3.2 The Supplier Shall Meet Customer Requirements
Once customer requirements are known, the supplier must determine how to produce a satisfactory product. The
resources available to build the product must be considered, including personnel, materials, tools, manufacturing and
assembly processes, equipment, facilities, software, organizational processes, technology, in-service support, money,
and time. These resources must be characterized for their capabilities and limitations. With the knowledge of the product
requirements, conditions of use, and resource capabilities and limitations, it must be determined whether the product will
fulfill its requirements. This activity is an essential step that provides a risk assessment and determines the focus areas
for managing it. Having identified risks, the supplier then must design the product (and process) by mitigating these risks
through design and process innovation, exploratory development, decision making on serviceability and support issues,
as well as determination of manufacturing and assembly process control issues. Thus, the activities defining this JA1010
program requirement include:
a. Characterize Resources
b. Assess and Manage Risk
c. Design to Achieve Maintainability
1.2.3.3 The Supplier Shall Assure That Customer Requirements Have Been Met
The supplier needs to demonstrate to the customer’s satisfaction that the product meets requirements, thus qualifying the
product design. Effort should be expended from the system concept through the hardware development phase to:
(1) determine the accuracy of and update the analytical (predicted) data obtained from maintainability engineering
analysis; (2) identify maintainability design deficiencies for resolution; and (3) gain progressive assurance that the
maintainability of the product can be achieved and demonstrated. Complete documentation must be maintained to show
customers that the product can indeed satisfy their needs. The generation of information from the Maintainability Program
can be accumulated in the Maintainability Case (MC) described in Section 5, which will provide the customer with
progressive assurance that the product will meet the customer requirements.
The supplier should also develop a closed-loop feedback system that channels information about the product during the
development process, as well as after it has been sold to various groups within the supplier’s organization. Thus, the
activities defining this JA1010 Program Requirement include:
a. Qualify the Product and Process
b. Establish Process Control
c. Pursue Continuous Process Improvement
d. Establish Data Collection and Reporting
1.2.4 Managerial Issues in Maintainable Product Development
Table 1 depicts the framework for the development of a maintainable product. In order for companies to succeed in
applying the framework, certain managerial and organizational issues should be addressed. The most significant among
these are, the nature of the supplier-customer dialogue, which is essential for a successful program. The creation of self
managed, cross-functional product development teams, and the management of supply chains should also be
considered.
1.2.4.1 Supplier-Customer Dialogue
The key to successful maintainability programs (product development in general) is the quality of the supplier-customer
dialogue. To be successful, an ideal supplier-customer dialogue should be initiated by the supplier as early as possible in
the product development cycle and continue throughout the entire product life cycle. The output from the dialogue will
vary in complexity based on product and organizational requirements. As applicable, typical outputs would include the
following:
a. Details of the supplier-customer dialogue itself (roles, responsibilities, participants, authorization, frequency, duration
and modes of communication).
b. Documentation of requirements.
c. Contractual issues (program costs, repair costs, support costs, metrics, liability, warranty, delivery, approved sources,
applicable standards).
d. Full and adequate definition of all product requirements (conditions of use, operating environment, maintenance and
service, in-service support, product specification, and the customer/supplier definition of product failure).
e. Conflict Resolution
f. Trade-off Procedure
The details and complexity of the dialogue and requirements will of course vary. The supplier-customer dialogue is the
first step in developing the maintainability program. However, it continues throughout the length of the product
development and life cycle.
1.2.4.2 Product Development Teams
Up until the mid-1980s, a sequential product development model was standard practice throughout industry. Each step in
the new product development process was handled by a single functional specialty. Such an approach became less and
less viable in the emerging faster-paced high-tech arena. The new approach is to establish a product development team
with representatives from all the relevant functions working together from the start. Some industries carry this concept
even further by giving these cross-functional teams much higher responsibility and authority in making decisions. Such
“highly trained group of employees, fully responsible for turning out a well defined segment of finished work” is called self-
managed teams.
The product development team is entrusted to guide new products through development. By placing decision making in
the hands of the team, companies better coordinate product developments, improve product quality and time to market.
The combination of several disciplines into one group expands the overall skill set of the team. Not only do the group
members actively take advantage of group dynamics and collective thinking, but the diversity of skills present makes it
possible to view issues from different perspectives, evaluate them, and assign and follow up on tasks within the team.
The long association builds camaraderie between team members, gives each person a better appreciation for the others’
jobs, and helps members clearly see the value of their work to the project.
1.2.4.3 Supply Chain Partnering
Over the last decade, manufacturers have cut their production and component costs dramatically by overhauling their
supplier bases. Suppliers now take responsibility for just-in-time (JIT) delivery of parts, part quality, reliability and
maintainability, reduction of inventory costs, mitigation of defects, and efficiency improvement of their manufacturing and
assembly lines. However, many companies are now taking “supplier partnering” and “supplier alliances” into an even
more advanced form of supply chain management called “supplier integration.” These companies focus on aligning with
all the critical suppliers in their supply chain to achieve higher quality, reliability and maintainability, faster new product
development, improved use of technology, reduced time to market, minimized investment in resources, and reduction in
product development costs.
Suppliers increasingly indicate that they prefer involvement early in the development process. Suppliers get involved in
product design, support quality initiatives, increase profitability, provide schedule sharing opportunities, respond to cost
reduction ideas, maintain consistent communications and feedback, have a well organized crisis management/response
system, and are, in general, totally committed to the partnership.
1.2.5 Objectives of a Maintainability Engineering Program
The objectives of a Maintainability Program are accomplished by implementing the six steps outlined in the following
paragraphs. Each objective should be analyzed and tailored to the level applicable for the product or system being
developed for a customer. The supplier shall implement and conduct a Maintainability Program reflecting the agreed upon
tailoring of the objectives.
1.2.5.1 Integrate Maintainability with the Systems Engineering Process
Systems engineering is a top down iterative process involving definition of requirements, flow down of requirements,
functional analysis, allocation, design, test and evaluation. By integrating the maintainability activities into the design of
both the product and the manufacturing processes for creating the product, maintainability requirements will be addressed
concurrently with other requirements. The up-front integration of maintainability issues/activities/requirements with
engineering and manufacturing design activities will help to reduce program costs and schedules by minimizing duplicate
efforts and re-designs. An integrated systems approach is essential because maintainability is a major product
characteristic.
1.2.5.2 Product Life-Cycle Cost
The in-service/field support cost factors can far outweigh the development and acquisition costs with most military and
many commercial products. Maintainability and other design and logistics disciplines are now well developed for ensuring
that supportability and operating cost factors are identified and considered from concept and throughout the life cycle of
the equipment, so that they influence the design with the aim of optimizing the life cycle costs. Proper Maintainability
influence on product designs includes support considerations which influence the equipment concept and design,
identifies the necessary support needed to field the equipment and provides an integrated process for delivering
supportable equipment and support infrastructure.
1.2.5.3 Thoroughly Understand the Design
Thoroughly understanding the design is essential to making the final product maintainable. Accessibility, human factors,
diagnostic capability, and repair times must be known or determined with as much certainty as time, budget, and technical
knowledge allow. Understanding the maintenance required to support the product during use will aid in identifying the
potential shortcomings in design relative to maintainability, supportability and logistics. These shortcomings should be
addressed during the initial design phase to ensure all aspects of the product life cycle will be successfully handled,
including the spares (replacement parts), special tools (if any are required), maintenance technician training and product
disposal.
1.2.5.4 Design for Desired Level of Maintainability
A maintainable product is the result of a conscious and dedicated effort to incorporate design features that make
preventive and corrective maintenance easy, safe, and economical in terms of time and resources. It is the responsibility
of the product development team to design the product so that it can be maintained within the constraints of time and
resources.
One aspect of maintainability is pro-active failure detection, which allows identification of a deteriorating product
performance prior to an actual malfunction. The hardware, software, or other means, used to detect that a malfunction is
about to occur are collectively called prognostics. This leads to a reduction in malfunctions occurring at indeterminate
times. The replacement of items can be scheduled, with all the necessary resources, to a time and place convenient to
both the user and maintainer, thus reducing down time. The pre-emptive nature of the actions effectively moves corrective
maintenance to preventive maintenance, thereby minimizing secondary consequences.
Another aspect is determining when a product has malfunctioned and why. The hardware, software, or other documented
means used to determine that a malfunction has occurred and to isolate the cause of the malfunction are collectively
called diagnostics. As products become more complex, diagnostics capability becomes an essential and critical part of
design. For such products, diagnostics is a driver of maintainability because identifying and isolating a problem to its root
cause often accounts for the majority of repair time. The most effective diagnostic capability encompasses built-in test
(BIT), which includes any automatic and/or semi-automatic testing. Also included in this capability are manual testing,
maintenance aids, and technical information. The necessary level of training and experience of personnel should be
identified at the earliest phase of the program along with maintenance aids.
1.2.5.5 Validate Maintainability
Throughout the design process, continual assessment of maintainability should take place through qualitative and
quantitative analysis. Computer simulation of maintenance can be a useful tool, which allows the maintainability
characteristics of a design to be “evaluated” before any model, or prototype is even constructed. Maintainability and
testability demonstrations can be conducted to show whether or not a product possesses the requisite characteristics.
The specific approach used for demonstrations should be agreed upon between the customer and supplier and be
identified in the program plan.
1.2.5.6 Monitor Maintainability
It is important for the customer, the supplier, or both to monitor the maintainability of the product in actual use. This
monitoring may be done through tracking warranty data, field experience, collecting specialized information, customer
complaints, and surveys. Monitoring and subsequent analysis of the data is done to identify maintainability
issues/problems, identify needed changes in policies, procedures, processes or design and to identify and document
lessons learned.strRefField
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